Stethoscope



Jan. 28, 1947. J. BRANDENBURG 2,414,850

S'TET'HOSCOPE Filed March 14; 1944 INVENTOR I Juuus BRANDENBUKG JJM MW.

ATTORNEY Patented Jan. 28, 1947 STETHOSCOPE Julius Brandenburg, New York, N. Y., assignor to Brandenburg Instrument Co. 1110., a corporation of New York Application March 14, 1944, Serial No. 526,357

7 Claims.

This invention relates to Stethoscopes.

Broadly, it is object of my invention to provide a stethoscope which gives improved amplification of the pulsation of heart murmurs.

More particularly, an object of my invention is to provide a stethoscope which equalizes the tone of heart murmurs, giving a more uniform pitch, at the same time providing a certain amount of reflection of sound. within the housing of the stethoscope.

A further object of my invention is to provide a, pair of parallel diaphragms placed at such an angle within the housing of the stethoscope so that vibration of sound or other disturbances is eliminated, such as when the stethoscope is moved by the physician over the skin or hairs of the body. Since the murmurs of the thoracic viscera are only faintly audible it is of the utmost importance to obtain better vibration of the resonance plates. I have therefore provided a pair of angular and parallel resonance plates, one with holes and the other with slots for facilitating movement of the sound waves and to provide better vibration in order to give a more definite sound tone with greater resonance.

Another object is to provide a stethoscope which is easily assembled so that the parts may be readily replaced in the event it should become necessary so to do.

For a fuller understanding of the nature and objects of my invention, reference is bad to the following detailed description in connection with the accompanying drawing, in which Fig. 1 is a vertical longitudinal View, with parts partly broken away. Fig 2, partly in section, is a front elevation of the stethoscope head, showing the parts partly broken away.

Referring to the drawing, numeral l represents the side housing wall of the stethoscope having an internal thread H and an internal straight wall l2. Below the thread i there is an internal shoulder is which acts as a seat for a flange M of upper diaphragm iii. Housing in also has an external shoulder It which may act as a stop for the knurled clamping ring ll. Below shoulder it the lower housing portion has an external thread is to receive the threaded clamping ring [1.

Clamping ring H has an internal thread is which coacts with the external thread It and has an angular shoulder 26 for clamping an outer diaphragm 2! within a space created by the angular shoulder 29 and the parallel angular edge 22 of the lower portion of the housing l0. Diaphragm 2| is preferably made of Celluloid. However, this diaphragm may also be made of exceptionally thin metal or other types of plastic.

At the upper portion of the stethoscope a cap portion 23 has a depending annular flange 24 with an upper smooth face 25 and a lower external threaded portion 26 'coacting with the internal threaded portion I! of the housing The depending flange 2 of cap 23 has a horizontal end 27 which clamps the flange i i of the upper diaphragm I5 against the internal shoulder is of the housing wall H1. The inner wall of cap 23 and lower. portion of housing it are in vertical alignment. The upper portion of cap "3 has a raised portion 28 in order to provide su cient material for an internally threaded op ing 28 to receive the lower external threaded portion 30 of Y member 3i.

Y member 32 is hollow throughout with raised portions 45-46 at the upper extremities to receive and hold the rubber tubes which are placed over the angular arms of the Y member iii. The lower end of Y member 3i is formed so that it is flush with the inside of cap 23.

Behind outer diaphragm 2i and clamped by a flange 32 between the angular shoulder 2% of the clamping ring I! and the angular edge 22 of the lower portion ofthe housing, an intermediate diaphragm 33 is firmly positioned. Diaphragm 33 has an outer flange 32 and a vertical portion .34 which rests against the inner wall or" the lower portion of housing it. It is then bent in a frusto-conical shape having an angular portion 35 and a central opening 852. A series of small holes 31 are spaced at regular intervals around the angular portion 35 of the intermediate diaphragm 33.

As heretofore described, upper diaphragm i5 is firmly fixed in position by its flange it clamped between the lower end 2? of the depending fiange 2 1 and the internal shoulder l3. The diaphragm is then bent upward with a vertical portion 38 resting against the inner wall of the annular flange 24. It is then bent in a frusto-conical shape with an angular wall as which is in parallel relationship to angular wall oi the intermediate diaphragm 33. The upper portion of upper diaphragm l5 has a small horizontal flange 40 and a central opening ll. The annular wall 39 has a series of slots 62 which lead into the central opening 4 l.

The upper diaphragm l5 and the intermediate diaphragm 33 are made preferably of exceptionally thin metal so that they are sensitive to the movement of sound waves. It should be noted that the small horizontal flange 48 of the upper diaphragm I 5 is not in contact with the inner wall of the cap 23 in order to permit free vibration of the upper diaphragm.

When stethoscope is moved over the skin of a person the outer diaphragm 2| receives the vibrations and transmits the same to the interior of the chamber, the sound entering the vortex in the intermediate diaphragm 33 and passes through openings 32 and the central opening 36 and then is received by the upper diaphragm l5 which further directs the vibrations toward the central opening H of the upper diaphragm, and thence through the hollow channels of Y member 3i and thence throughthe rubber tubes (not shown) leading to the mediate and upper diaphragms 33 and I5, re spectively, retards reflection of the sound between the inner walls of the housing and cap and direct the sound the walls of both the intermediate and upper diaphragm vibrate in unison and-create a lower and more uniform pitch which is more readily discerned by the person using the stethoscope.

It is obvious that various changes and modifi cations may be made in the various details of constructions without departing from the general spirit of the invention as set forth in the appended claims,

I claim:

l. A stethoscope comprising a transmitter head, said head having a'sound receiving chamber, a pair of diaphragms conically shaped with central openings and spaced in parallel relationship to one another within said chamber, an outer diaphragm for transmitting sound waves into said chamber and a passageway for leading the sound from said chamber.

2. A stethoscope comprising a transmitting head, said head having a sound receiving chamber, an upper diaphragm having a central opening, and slotted angular Walls, an intermediate diaphragm having openings in an angular wall and a central opening, said intermediate and upper diaphragms being fixed within said chamber and the angular walls of said diaphragms being'in parallel relation, an outer diaphragm for transmitting sound to said inner chamber, and a passageway leading from said chamber. a

3. A stethoscope comprising a transmitting head, said head having a housing and a cap an outer diaphragm, an intermediate diaphragm, an

ear pieces. The intertoward the bottom of the Y' member,

4 upper diaphragm, said housing having an annular ring for clamping an outer diaphragm and an intermediate diaphragm within said housing, an upper diaphragm fixed between said intermediate diaphragm and said cap, said intermediate diaphragm and upper diaphragm having central openings and angular walls in parallel relation to one another and a passagewy leading from said chamber.

4. A stethoscope comprising a transmitting head having a sound receiving chamber, said head I having a housing, a cap with a depending annular flange fitted within said housing, an outer clamping ring fitted upon said housing opposite said cap, said clamping ring holding an outer diaphragm and an" intermediate diaphragm within said chamber, saidcap holding an upper diaphragm within said chamber, said intermediate and upper diaphragms having center openings and angular walls spaced in parallel relation to one another, and a central passageway leading from said chamber.

5. A stethoscope comprising a transmitting head, said head having a hollow chamber, a pair of frusto-conical shaped resonance plates within said chamber in parallel relationship to one another, said resonance plates having central openings, an outer diaphragm for transmitting sound waves into said chamber, and a Y-member with hollow passageways for leading the sound from said chamber.

6. A stethoscope comprising a transmitting head with a chamber, said head having an open ing at one end, a hollow terminal leading into said opening, a pair of angular resonance plates spaced apart in parallel relation, said plates having central openings, and an outer diaphragm at the opposite end for leading sound waves into said chamber. 7

7. A stethoscope having a transmitting head and a chamber, an upper resonance plate within said chamber and an intermediate resonance plate in parallel relation to said upper resonance plate, said upper and intermediate resonance plates having angular walls with openings there on, each of said plates having a central opening, a flexible diaphragm for leading sound waves into said chamber, and an opening at the opposite end of said housing for leading sound waves out of said chamber.

JULIUS BRANDENBURG. 

